Cembranoids from a Chinese Collection of the Soft Coral Lobophytum crassum
Min Zhao,
Shimiao Cheng,
Weiping Yuan,
Yiyuan Xi,
Xiubao Li,
Jianyong Dong,
Kexin Huang,
Kirk R. Gustafson,
Pengcheng Yan
Affiliations
Min Zhao
School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
Shimiao Cheng
The Fifth Affiliated Hospital, Wenzhou Medical University, Lishui 323000, China
Weiping Yuan
School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
Yiyuan Xi
School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
Xiubao Li
Key Laboratory of Marine Bio-Resources Sustainable Utilization, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
Jianyong Dong
School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
Kexin Huang
School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
Kirk R. Gustafson
Molecular Targets Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
Pengcheng Yan
School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
Ten new cembrane-based diterpenes, locrassumins A–G (1–7), (–)-laevigatol B (8), (–)-isosarcophine (9), and (–)-7R,8S-dihydroxydeepoxysarcophytoxide (10), were isolated from a South China Sea collection of the soft coral Lobophytum crassum, together with eight known analogues (11–18). The structures of the new compounds were determined by extensive spectroscopic analysis and by comparison with previously reported data. Locrassumin C (3) possesses an unprecedented tetradecahydrobenzo[3,4]cyclobuta[1,2][8]annulene ring system. Compounds 1, 7, 12, 13, and 17 exhibited moderate inhibition against lipopolysaccharide (LPS)-induced nitric oxide (NO) production with IC50 values of 8–24 μM.
